Well, I managed to get my KJ66 I built back in May/June 2003 out and do the following...
1- rebalance the rotor assembly even better than before
2- paint the outer case with high temp silver paint (and bake in the bbq at 650 for 1 hour)
3- exchange thepreload spring for a longer, stronger one.
WHen I fisnihed running the engine last, I had accumulated about 3 hours run time. It still had an annoying high pitch even though it felt quite smooth at 120,000 rpm, so thats why I re did the balance. I also thought the rear bearing was slipping a little, and I was goign to use an O ring in the shaft tunnel, but after I measured my preload (was 3kg, supposed to be 4.5 to 5 kg) I decided I would try a stronger spring first. SHould hopefully work. ANd I noticed that the case outer that I bead blasted was pretty susceptible to rusting so I decided a coat of manifold paint would fix that.
I hope to run it again within a month and report back on the results. Hope that I can fly this in my S Reaper next season if I can get at least 14 to 16 lbs thrust...
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Andrew Coholic -MAAC #26287L
1/2A to giant scale, IMAC, SAM, R/C sport, turbine jets, Heli's...
if its got a wing or two and an engine - I like it!
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